Question 5.17: What does the system shown in Figure 5-31 do?

Figure 5-31 shows the block diagram of a light detection and ranging system (LiDAR). Similar to radar (radio direction and ranging), a LiDAR system transmits and receives electromagnetic (EM) waves. Operating at frequencies from near-infrared to visible blue light, this system can provide high-resolution topographical mapping, which can be used in applications such as vehicle adaptive cruise control and collision avoidance systems.
Controlled high-frequency pulses are applied to the laser. The laser’s emitted light waves are focused by a lens to create a narrow beam. When this light beam hits a target, it is reflected back and focused on a photodiode detector. The small photodiode output is amplified and converted to a proper signal for the control and processing block. By using several stacked lasers and horizontal scanning methods, a detailed image can be produced.